Humidifier



May 7, 1935. F. N. SMITH HUMIDIFIER Filed April 2, 1954 Ill JINV-ENTOQRI' i'rr/b 11 5/27/72 EM K X ATTORNEYS Patented May 7, 1935 UNITED STATES PATENT OFFICE numnmmn Ferris N. Smith; GrandlwpidsfMiclh- Application April 1934,9S8fi3FNO. "11184690 .28 Claims.

mainobjects of this invention are:

Fir-st,--to provide an automatic-ally controlled steam generatorwhich is well adapted foruse in connection with a house heating system.

Second, to'- provide a steam-generatorof this character which may be quiekly and easily installed in a boiler -or furnace.

Third, to 'provide an automatically controlled steam=-generator in whichthe amount of steam delivered-'mayhe accurately regulated.

Fourthpto provide a val-vecontrol means for a steam generator in which the valve is opened with-a snap action, thereby minimizing scoring of the valve-seat and preventing clogging there- Objects relating "to details "and economies -o'f my invention will appear from the-descriptionto follow. The invention is defined and pointed out in the claims.

A structure which is a preferred embodiment of myinvention is illustrated in*theaccompanyir-ig drawing, in which:

Figu l isa fragmentary'perspective -viewof portionsof 'a *heat-ingsystem shown mainly in conventional form with 'a 'hu-midif-ying apparatus embodying myimprovements inoperative relation thereto.

Fig32' is anenlarged view inside elevation of-an outerend portion of a-commercial embodimentof my invention, portions 'being broken 'away and shown in 'longitudina'l section.

ZE'lig ZAiS-avieWof theinner-endportion similar to amide-continuation of'Fig.

"In the accompanying drawing, -numeral '1 represents -a heating furnace or boi-ler, =2 the fire or combustion chamber door, and 3 the door frame. 4 represents :a #rad-iatorand 5 --a steam distributing :head disposed ad-j acen'tthe-- radiator so nthat i the air curren'tsset up -by the radiator will. distribute :the steam or vapor-delivered tothe (Cl. .12245.L1)

The head-=memberis providedwvith awalve unit t5 hawing:a plugdikeend fitting fitfirthreadedfinto the erila-rged portion of g the head memberend held fin place by the lock nut I?! The :fitting 148 has a valve seatiIB ithreaded in the centralibore 5 13azconnectingatheiinlet :chamber M I and ithevalve chamber zll.

The :vailve :unit-ris provided with -.a screen :22 through which .ithe zwater must mass 'ibefore it enters:the.=valvechamber r20. The valve :12l :is ii normally closedi by the ipressureof the inletm; ter .assisted iby 1 the-compression .spring :23 in time valveichamber. e

The cylindnical @plunger, or slide enacts-with the push rod 24 extending through (the bore 1x6 1;; to =open= the .:valve' 2.0! awheni-theisleeve is advanced. The zendiof "the zplungerncoactingvwith ithe z-push rod 24 Y is .provided with .a "plurality of 1 ports 2.25 for ithe passage of water 'therethrough. 2011 ::the tubular. sectioned, mount :atguarden ifor :shielding :ethe :valve unit :al 5 170 prevent the .samefrom heingtadamagedsashystrikingritiwithia-shevelused in throwing :ifiuel into .--the :fu-rnace through :the door frame when :the device is :.installed :in exnosedmosition as inrFig. 1. 2,5

"Withinnthe :boiler tandwdisposed concentrically thereof, Itmount a'tiibular thermostatic .wmember 2 1 threaded mithinxtheireduced rportion :flcof headmemher soathatitzis supported iithereby. at itsrinneriz end with iitsouter send :spaced from=;the eerrtnal.-,stud .'Z91ofithe-.c1osure :plug 8. A coactingatubular:thermostatiwmember:onelementwmis thneadedrzup Ollith outer; end; of :theathemiostatic memberczl ,aithe outenend :Of the. memb erzllhbeing sleeved over the stud 29 as shownwwherebyr it 5' supporteddzhereby and furnishesamefiectivefheat conductingicontactiibetween.ztherwall of the tem'it and the thermostatic element. The studiH-z-iis tapered has shown and {the :outer send 101 .the thermostatic elementxwsis-zpnovided withoutlet c0 ports-:31 zforcthe passage of mater:deliveredZbysthe innerzthermostatic; member :21. "iThe router ztheramosatic ,member 3'30 11543150 provided with sports d2: adjacent the. outer :end :of xtheiinnenther'mostatic .=;member 2.:1.

"i'heiainnericendjof :the thermostatic :memberifll iskeyediorrpinnedtotthe plun erili4chymieansnot the transverse: pin;33,; the :reducediportion 28 mt .theiheawmember I abeing :providedrwith opposed flongitudinalslotsifl therefor. .Azlostimotionieon- 5 neotiomis thus .providedihetween the thermostatic elements at their: inner iendsisaiidtelements .connectediiat :-their.-: outer ends. Thewoncentric relation.- of ilbhe them'iostatic :elements rat innemendssisamaintaine'dibyntherneduced portion i nections described.

28 of the head member I, the inner end of the thermostatic member 30 being freely movable relative to the reduced portion 28 of the head.

The relation of the valve 2! with the thermostatic element 30 may be adjusted by loosenin the lock nut I! and rotating the fitting l6 of the valve unit.

The boiler unit is mounted on the supporting plate 35 which may be bolted to the frame of the door of the furnace so that the boiler is supported in suitable position in the combustion chamber. Water is supplied to the device through the connection l2 and its delivery to the boiler is controlled by the valve.

The boiler has a discharge connection 36 preferably at its inner end and connected to the diffuser head as illustrated in Figfl, a separator trap 3'! being preferably used in'this connection.

The thermostatic elements are of different co-. eificients of expansion, the outer element preferably having arelatively high coefficient of expansionv and the inner element a relatively low coefficient of expansion. Iron for the inner thermostatic'element 21 and brass for the outer thermostatic element 30 nicely satisfy this requirement. Thus,-when the thermostatic elements expand to a predetermined degree, the expansion of the. outer element cracks the valve admitting water into the valve chamber and thence into the inner thermostatic element. The latter has been expanded to a substantial degree, but relatively less than theouter element and the incoming water acting on the inner element causes it to contract quite rapidly and fully opens the valve with a snap action.

' The water is discharged from the inner element into the boiler and the outer thermostatic element causing the outer thermostatic element to contract, whereupon the valve is closed byits spring a'n'd'the pressure on the water behind it. This action' is quite rapid and the water is supplied to the boiler in approximately measured amounts soit may be quickly converted to steam and delivered to the distributor head through the con- It will be understood that when the fire is low the device 'does not operate, but that is a desired condition as it is not desirable to discharge steam intoa cold room.

I have illustrated and described my improvements in an'embodiment which I have found very practical. I have not attempted to illustrate or describe other embodiments or adaptations, as it is believed this disclosure will enable those skilled in the art to'embody or adapt myimprovements as may be desired'.. I

. Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In an automatically controlled steam generator, the combination of a boiler comprising a tube-like body member, a closure plug threaded into the outer end of said body member and having a central inwardly projecting stud, closure means including a head member threaded into the inner end of said body member and having an inlet chamber, the boiler having a discharge adjacent its inner end, a valve unit associated with said head member, and having a central bore opening to said inlet chamber and providedwith a valve seat, a "spring closed valve coacting with said valve seat, a plunger mounted in said inlet chamber for longitudinal movement, a push rod disposed in said bore between said plunger and said valve for opening the latter when the plungeris advanced, a tubular inner thermostatic element mounted on said head member concentrically of said boiler and opening at its inner end to said inlet chamber and at its outer end to said boiler, an outer thermostatic element mounted on the outer end of said inner thermostatic element and having its outer end sleeved over said stud and its inner end sleeved over said head member, the outer thermostatic element having Wall ports in its outer end, and a transverse pin connecting the inner end of said outer thermostatic element to said plunger, the head member having opposed longitudinal slots for the passage of said pin whereby the plunger is advanced by the expansion of said outer thermostatic element and by the contraction of said inner thermostatic element.

2. In an automatically controlled steam generator, the combination of a boiler comprising a body member, a closure plug threaded into the outer end of said body member and having a central inwardly projecting stud, closure means including a head member threaded into the inner end of said body member and having an inlet chamber, the boiler having a discharge adjacent its inner end, a valve unit associated with said head member and having a central bore opening to said inlet chamber and providedwith a valve seat, a valve coacting with said valve seat, a plunger mounted in said inlet chamber for longitudinal movement, a push rod disposed in said bore between said plunger and said valve for opening the latter when the plunger is advanced, a tubular inner thermostatic element mounted on said head member and opening at its inner end to said inlet chamber and at its outer end to said boiler, an outer thermostatic element mounted on the outer end of said inner thermostatic element and having its outer end sleeved over said stud and its inner end sleeved over said'head member, and a transverse pin connecting the inner end of said outer thermostatic element to said plunger, the head member having opposed longitudinal slots for the passage of said pin whereby the plunger is advanced by the expansion of said outer thermostatic element and by the contrac-- tion of said inner thermostatic element.

7 3. In an automatically controlled steam generator, the combination of a boiler comprising a tube-like body member, a closure plug mounted in the outer end of said body member and having an inwardly projecting stud, closure means including a head member mounted in the inner end of said body member and having an inlet chamber, the boiler having a discharge adjacent its inner end, a valve unit associated with said head member and having a bore opening to said inlet chamber and provided with a valve seat, a valve coacting with said valve seat, a plunger'mounted in said inlet chamber for longitudinal movement, means disposed in said bore between said plunger and said valve for opening the latter when the plunger is advanced, a tubular inner thermostatic element mounted on said head member and opening at its inner end to said inlet chamber and at its outer end to said boiler, an outer thermostatic element mounted on the outer end of said inner thermostatic element and having its outer end sleeved over said stud and its inner end sleeved over'said head memben'the outer thermostatic element having wall ports adjacent its outer end, and means connecting the inner end of said outer thermostatic element to said plunger, the head member having slots for the passage of said connecting' means wherebythe plunger is advanced by the expansion-of 's'aid outer-thermostatic element and by the contraction of said inner thermostatic element.

*4. In ran automatically controlled steam genorator, the combination :of a boiler comprising a tube lilte body member closed at its outer=end, closure means including ahead member mounted in the inner "end of "said body member and an inlet chamber, the boiler having a discharge adjacent its inner end, a valve unit associatedwith said headmember and having a central bore op'eningto said inlet "chamber and provided with a 'valve seat, a spring closed valve coacting with said valve seat, aplunger -mounted in said inlet "chamber for longitudinal movement, .9. push :ro'd disposed through said here between -'saidLplunger and said valve fo'r open ing the latter when the plunger :is advanced, a tubular inner "thermostatic element mounted onsaid headmember concentrically of said boiler and opening at its inner end to said inlet chamber and at its outer end "to "said boiler, an outer thermostatic element mounted on the outer 'endof said inner'thermost'atic element and havin'gits inner end sleeved over'said head'member, the'outer thermostatic element having wall ports adjacent its outer end, and a transverse pin connecting the inner end of said outer thermostatic element to said plunger; the head memher having opposed longitudinal slots for the passage of said pin whereby the plunger is advanced by the expansion of said outer thermostatic -'element and by the contraction of said inner thermostatic element.

5. In an automatically controlled steam generator, the combination of a boiler comprising a tube-like body member, a closure plug threaded into the outer end of said body member and having a central inwardly projecting stud, means including a head member threaded into the inner end ofsaid 'bodymember and having an inwardly'projec'ting central portion of reduced diameter, a tubular inner thermostatic element mounted *on the reduced portion of said head member concentrically of said boiler and opening at its outer end spaced relation to said stud, a tubular outer thermostatic element sleeved at-its ends over said stud and the areduced portion'of said headmemberand having a threaded connection with the outer end of said inner thermostatic element, the thermostatic elements being disposed concentrically and-the outer element having wall ports adjacent both ends of its threaded connection with the outer end of said inner thermostatic element, a plunger mounted forlongitudinal mo'vem'entin said head memberandkeyedto the inner end'ofsaidouter thermostatic element for actuation thereby, a valve -'unit"having anendfitting threaded into said head -member-for longitudinal adjustment and "having :a central longitudinal borep'rovided witha valve'seat at one end, a springclosed valve coasting with said-seat, and a pushrod disposed between said-plunger and said valve insaid bore fornpening the "valve when the plunger is advanced.

-6. In an automatically controlled steam genorator, the-combination of a boiler comprising a tube-like body member, a closure plug threaded intothe'outer end of saidbody member andhaving a='central inwardly projecting s'tud, means including a-head member threaded into the inner endof "said body member andhavingan inwardly projecting central :,portion of: reduced diameter, a

tubular inner thermostatic element unnuntednn the reduced portion of :said head meinb'e'r eencentrieally o'f saidboiler'and opening at slower end in spaced'relation to saiidstud, tubular outer thermostatic elemen't sleeved at its-ends over said stud and the reduced portion of 'sa'id head member and having a I connection with the outer end of said inner thermostatic elemerit; the thermostatic elements being disposed :concentrically and the outer element ha'vi-ng wall p'orts adjacent both ends of its connection "with the outer end of said inner thermostatic elem'ent a plunger mounted for longitudinal movement in said head member and keyed to the inner-end-of said outer thermostatic "element i'or aetua tion thereby, a valve unit having an end fitting bread 4 ed into said head member and having :a c'entral longitudinal b'ore provided with a valveseat-at one end, a valve coacting with said seat, and 'a push ro'd disposed :between said plunger and said valve in said bore for opening the valve when the plunger is advanced. a

'7. In an automatically controlled steem generator, the combination of a boiler bomprisinga tube-like body-member, a closureplug th'readed into the outer end of said body memberand having a central inwardly projecting stud, means including a head member threaded ihto'the inn'er end of said body member and having an inwardly projecting central portion of reduced diameter, a tubular inner thermostatic elemen't mounted on the reduced portionof said head member concentrically of said boiler and opening at its outer end in spaced relation to said stud, a tubular outer thermostatic element sleeved at its ends over said stud and -the reduced portion of said head member and having a connection with the outer end of said inner thermostatic element, a plunger --mounted for longitudinal movement in said headmember and keyed to the inner end of said outerthermostatic element for actuation thereby, a valve unit having an and fitting threaded-into said'headmemher and having a central longitudinal b'ore pr ovided'with a valveseat at one end, a valve eoacting with said seat, and a push rod disposed'between-said plunger and said valve in said bore for opening the valve when the plunger is advanced.

8 In an automatically controlled steam generator, the combination of ab'oile'r comprising'a tube-like body member, a closure plug mounted in the outer end of said body member and having an inwardly projecting tapered stud, means including a head member mounted in the 'inner end of said bodyimember and having an inwardly projecting jportion of reduced diameter, a tubular inner thermostatic elem'enth'a'vinga relatively low coefficien't of linear expansion mount ed' on the reduced portion of said head member and opening at its outer end in spaced relation to said stud, a tubular outer thermostatic element having a relatively high coefficient of linear =expansion sleeved at its ends over said-stud and t'he bore, provided with a valve seatatone-end a spring closed valve coacting with said seat, a push rod disposed between said plunger and said valve in said bore for openingthevalve when the plunger is advanced, and a cylindrical shield or guard mounted on the inner end of said body member for protecting said valve unit.

1 ,9. In an automatically controlled steam generator, the combination of a boiler comprising a tube-like body member, a closure plug mounted in the outer end of said body member and having an inwardly projecting tapered stud, means including a head member mounted in the inner end of said body member and having an inwardly projecting portion of reduced diameter, a tubular inner thermostatic element having a relatively low coefficient of linear expansion mounted on the reduced portion of said head member and opening at its outer end in spaced relation to said stud, a tubular outer thermostatic element having a relatively high coefiicient of linear expansion sleeved at its ends over said stud and the reduced portion of said head member and having a connection with the outer .end of said inner thermostatic element, the outer element having wall ports adjacent both ends of its connection with the outer end of said inner thermostatic element, a plunger mounted for longitudinal movement in said head member and keyed to the inner end of said outer thermostatic element for actuation thereby, a valve unit having an end fitting mounted in said head member for longitudinal adjustment and having a longitudinal bore provided with a valve seat at one end, a spring closed valve coacting with said seat, and a push roddisposed between said plunger and said valve in said bore for opening the valve when the plunger is advanced.

10. In an automatically controlled steamgenerator, the combination of a boiler comprising a tube-like body member closed at its outer end, means including a head member mounted in the inner end of said body member and having an in- Wardly projecting portion of reduced diameter, a tubular inner thermostatic element mounted on the reduced portion of said head member, a tubular outer thermostatic element sleeved at its inner end over said reduced portion of said head member and having a connection with the outer end of said inner thermostatic element, the outer element having wall ports adjacent both ends of its connection with the outer end of said inner thermostatic element, a plunger mounted for longitudinal movement in said head member and connected to the inner end of said outer thermostatic element for actuation thereby, a valve unit having an end fitting mounted in said head member for longitudinal adjustment and having a longitudinal bore provided with a valve seat at one end, a spring closed valve coacting with said seat, a push rod disposed between said plunger and said valve in said bore for opening the valve when the plunger is advanced, and a cylindrical shield or guard mounted on the inner end of said body member for protecting said valve unit.

11. Inan automatically controlled steam generator, the combination of a boiler comprising a tube-like body member closer at its outer end, means including a head member mounted in the inner end of said body member and having an inwardly projecting portion of reduced diameter, a tubular inner thermostatic element mounted on the reduced portion of said head member, a tubular outer thermostatic element sleeved at its inner end over said reduced portion of said head member and having a connection with the outer end of said'inner thermostatic element, the outer element having wall ports adjacent both ends of its connection with the outer end of said inner thermostatic element, a plunger mounted for longitudinal movement in said head member and connectedto the inner end of said outer thermostatic element for actuation thereby, a valve unit having an end fitting mounted in said head member for longitudinal adjustment and having a longitudinalbore provided with a valve seat at one end, a spring closed valve coacting with said seat, and a push rod disposed between said plunger and said valve in said bore for opening the Valve when the plunger is advanced.

12. In a structure of the class described, the combination with an elongated cylindrical boiler provided with a boiler chamber and an inlet chamber, of a valve chamber communicating with said inlet chamber through a port having a valve seat, a valve member slidable within said valve chamber and having a conical valve coacting with said seat, an inner tubular thermostatic element having a connection with the inner end of said boiler chamber and opening at its outer end to said boiler, an outer thermostatic element disposed concentrically relative to the inner thermostatic element and to the walls of the boiler and connected to the outer end of said inner thermostatic element, said outer thermostatic element having a relatively high coeificient of expansion compared to that of said inner thermostatic element, a plunger in said inlet chamber connected to the inner end of said outer thermostatic element, and a push rod extending through said port between said plunger and said valve.

13. In a structure of the class described, the combination with an elongated boiler provided with a boiler chamber and an inlet chamber, of a valve chamber communicating with said inlet chamber through a port having a valve seat, a valvev member slidable within said valve chamber and having a valve coacting with said seat, an inner tubular thermostatic element having a connection with the inner end of said boiler chamber and opening at'its outer end to said boiler, an outer thermostatic element connected to the outer end of said inner thermostatic element, said outer thermostatic element having a relatively high coefficient of expansion compared to that of said inner thermostatic element, and means in said inlet chamber connected to the inner end of said outer thermostatic element and extending through said port for coaction with said valve whereby the valve is cracked upon a predetermined expansion of said thermostatic elements and the inner element is subjected'to the incoming water whereby it contracts in advance of the contraction of the outer element to fully open the valve with asnap action. a

14. In an automatically controlled steam generator, the combination of an elongated cylindrical boiler, an inlet valve chamber provided with'an inlet port having a valve seat, a valve member slidable within'said valve chamber and havinga conical valve coacting with said seat, a thermostatic element connected to the valve by means including a push rod, a coacting tubular thermostatic element mounted at one end and having a connection to the outer end of said thermostatic element, the thermostatic element having a relatively low coefiicient of expansion, the valve being cracked upon a predetermined expansion of said thermostatic elements and the tubular element being subjected to the incoming water and being contracted in advance of the oozooms-5e acting element to fully open the valve with a snap action, and means acting to normally seat said valve.:

15;. 1115311 automatically controlled: steam generatonthecombination of an elongated boiler, an inlet valve chamber provided with an inlet port having a valve-seat, a valve member slidable within said valve chamber and'having a valve meeting with said seat, a thermostatic. element. connected' to the valve by means including a push rod; a coactingithermostatic element. mounted at one end? and having aconnection to the outer end ct said first named thermostatic element, the second named thermostatic element having a relatively low: coefiicient of expansion compared to said first named thermostatic element, the valve being cracked upon a predetermined expansionof saidthermostatic elements and the second named element beingisubjected to the incoming water and being contracted in advance of the first nained element to fully open the valve with a; snap action, and means acting tonormally seat said valve.

1 6. In a structure of the class described, the combination of a boiler, aninlet valve, a thermostatic element adjustablyassociated with said inlet valve, and a second thermostatic element mounted at the inner end thereof with respect to said inlet valve, said thermostatic elements having-- aconnection at their outer ends, the second thermostatic element having a relatively low coefficient of expansion and being subject to the incoming water whereby it contracts in advance of the contraction of the coacting thermostatic element.

17. In a structure of the class described, the combination of a boiler, an inlet valve, a thermostatic element associated with said inlet valve, and a second thermostatic element mounted at the inner end thereof with respect to said inlet valve, said thermostatic elements having a connection at their outer ends, the second thermo static element having a relatively low coefficient of expansion and being subject to the incoming water whereby it contracts in advance of the contraction of the coacting thermostatic element.

18. In a structure of the classdescribed, the combination of a boiler, an inlet valve, a thermostatic element adjustably associated with said inlet valve, and a second thermostatic element mounted at the inner end thereof with respect to said inlet valve, said thermostatic elements having a connection at their outer ends, the thermostatic elements having different coefficients of expansion, the element having the lowest coeificient of expansion being subject to the incoming water whereby it contracts in advance of the contraction of the coacting thermostatic element.

19. In a structure of the class described, the combination of a boiler, an inlet valve, a thermostatic element associated with said inlet valve, and a second thermostatic element mounted at the inner end thereof with respect to said inlet valve, said thermostatic elements having a connection at their outer ends, the thermostatic elements having different coefficients of expansion, the element having the lowest coefficient of expansion being subject to the incoming water whereby it contracts in advance of the contraction of the coacting thermostatic element.

20. In an automatically controlled steam generator, the combination of a tube-like boiler closed at its outer end and provided with an inwardly projecting central stud at its outer end and an outlet adjacent its inner end, a tubular inlet ment ber projecting centrally into the boiler at its inner end' a spring seated inlet valve delivering to said inlet member, a hollow plunger slidable'iwithin said inlet member and. having inlet openings" at its outer end, a: push rod operatively'associated with said plunger and inlet valve, a tubular inner thennostaticelementsecured to the inner end of said tubular inlet member, and an outer'tubular thermostatic element connected to the outer end of said inner thermostatic element and having sliding supporting engagement with said stud at the outer end of said boiler and telescoping en gagement with said inlet member and connected to said plunger whereby the plunger is actuated through the expansion and contraction ofsaid thermostatic elements. 21". In an automaticallycontrolled steam generator, the combination of a boiler, a tubular inlet member projecting centrally intothe boiler at its inner end, a spring seated inlet valve delivering to said inletmember, a hollow plunger slidable within said inlet member and having inlet openings at its outer end, a push rod'o'peratively associated with said plunger and inlet valve, a tubular inner thermostatic element secured to the-inner endof said tubular inlet'member, and an outer tubular thermostatic element connected to the outer end of saidinner thermostatic element and having telescoping engagement with said inlet member and connected to said plunger whereby the plunger is actuated through the expansion and contraction of said thermostatic elements. I

22. In an automatically controlled steam generator, the combination of a tube-like boiler provided with an inwardly projecting central stud at its outer end, a tubular member projecting centrally intothe boiler at its inner end, an inlet valve delivering to said inlet member, a plunger having a lost motion connection to said valve, an inner tubular thermostatic element mounted on the inner end of said tubular inlet member,

and an outer tubular thermostatic element secured upon the outer end of said inner thermostatic element and having sliding supporting engagement with said stud at the outer end of said boiler and telescoping engagement with said inlet member and connected to said plunger whereby the plunger is actuated through the expansion and contraction of said thermostatic elements.

23. In an automatically controlled steam generator, the combination of a boiler, a tubular member projecting centrally into the boiler at its inner end, an inlet valve delivering to said inlet member, a plunger having a lost motion connection to said valve, an inner tubular thermostatic element mounted on the inner end of said tubular inlet member, and an outer tubular thermostatic element secured upon the outer end of said inner thermostatic element and having telescoping engagement with said inlet member and connected to said plunger whereby the plunger is actuated through the expansion and contraction of said thermostatic elements.

24. In an automatically controlled steam generator, the combination of a tube-like boiler having an inlet at one end and an inwardly projecting central stud at its other end, a tubular inner thermostatic element disposed centrally of said tubular boiler and fixedly mounted at the inlet end thereof to receive fluid from said inlet, an

III

outer thermostatic element disposed concentri- V cured to the outer end thereof, the inner end of said outer thermostatic element being slidably supported, the outer thermostatic element being in telescoping engagement with said stud, a spring seated valve, and an operating connection for said outer thermostatic element to said valve. 25. In an automatically controlled steam generator, the combination of a tube-like boiler having an inlet at one end, a tubular inner thermostatic element disposed centrally of said tubular boiler and fixedly mounted at the inlet end thereof to receive fluid from said inlet, an outer thermostatic element disposed concentrically of said inner thermostatic element and secured to the outer end thereof, the inner end of said outer thermostatic element being slidably supported, a spring seated valve, and an operating connection for said outer thermostatic element of said valve.

26. In an automatically controlled steam generator, the combination of a boiler having a spring seated inlet valve, a tubular inner thermostatic element fixedly mounted at one end to receive fluid from said inlet valve, an outer thermostatic element disposed concentrically of said inner thermostatic element and secured to the outer end thereof, the inner end of said outer thermostatic element being slidably supported, and an operating connection for said outer thermostatic element to said valve including a push rod supported in operative relation to the valve and thermostatic element but being otherwise independent thereof.

27. In an automatically controlled steam generator, the combination with a boiler, a tubular inner thermostatic element disposed within said boiler and fixedly mounted at one end thereof, a water supply connection delivering to said thermostatic element and including an inlet valve, an outer thermostatic element connected to the outer end of said inner thermostatic element and having sliding heat-transferring supporting contact with an element of said boiler, the inner end of said outer thermostatic element being supported to permit longitudinal expansion of'the element, and an operating connection for said outer thermostatic element to said valve.

28. In an automatically controlled steam generator, the combination with a boiler, a tubular inner thermostatic element disposed within said boiler and fixedly mounted at one end thereof, a water supply connection delivering to said thermostatic element and including an inlet valve, an outer thermostatic element connected to the outer end of said inner thermostatic element, the inner end of said outer thermostatic element being supported to permit longitudinal expansion of the element, and an operating connection for said outer thermostatic element to said valve.

FERRIS N. SMITH. 

